Image-guided Targeted Doxorubicin Delivery With Hyperthermia to Optimize Loco-regional Control in Breast Cancer

Advances in systemic treatment led to improved overall survival in patients with metastatic breast cancer. Various studies suggest that by obtaining loco-regional control, overall survival in advanced disease can further be improved. Pre-operative chemotherapy can be used in metastatic breast cancer to make radical removal of the primary tumor feasible, while simultaneously maintaining control of already present metastatic sites. The doxorubicin and cyclophosphamide regimen (AC) is well-known both in (neo-)adjuvant setting as in treatment of metastatic breast cancer. At present, optimal local control in advanced breast cancer using adequate dosing of doxorubicin is hampered by its toxic systemic effects. Therefore the investigators aim to increase doxorubicin deposition in the primary tumor without interfering with systemic efficacy and toxicity, by combining lyso-thermosensitive liposomal doxorubicin (LTLD, ThermoDox) with local mild hyperthermia, induced by Magnetic Resonance guided High Intensity Focused Ultrasound (MR-HIFU). When heated to 40-43 ºC, ThermoDox releases a very high concentration of doxorubicin locally within seconds. In the absence of hyperthermia, ThermoDox leads to a similar biodistribution and antitumor efficacy to free doxorubicin. MR-HIFU allows for controlled heating of deep-seated tumors. This is a single-arm phase I feasibility study in 12 patients with de novo stage IV (distant metastasis at the time of diagnosis) her2-negative breast cancer, who have not received previous chemotherapy. The study treatment consists of up to 6 cycles at 21-day intervals of ThermoDox (50mg/m2) administered during MR-HIFU induced hyperthermia (60 minutes at 40-42 ᵒC) and cyclophosphamide (600 mg/m2) administered afterwards. A dedicated MR-HIFU breast system integrated with a clinical 1.5 Tesla Magnetic Resonance Imaging (MRI) scanner will be used for safe and controlled heating of the tumour. Primary endpoints are safety, tolerability and feasibility. Secondary endpoint is efficacy, assessed by radiological response of the local tumor and the distant metastases. In the Biobank side study, extra blood samples will be collected. These samples will be used for further research on not yet determined topics related to breast cancer.